net: Fix rxq ref counting

The rx->count reference is used to track reference counts to the
number of rx-queue kobjects created for the device.  This patch
eliminates initialization of the counter in netif_alloc_rx_queues
and instead increments the counter each time a kobject is created.
This is now symmetric with the decrement that is done when an object is
released.

Signed-off-by: Tom Herbert <therbert@google.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/dev.c

@@ -5024,7 +5024,6 @@ static int netif_alloc_rx_queues(struct net_device *dev)
 			return -ENOMEM;
 		}
 		dev->_rx = rx;
-		atomic_set(&rx->count, count);
 
 		/*
 		 * Set a pointer to first element in the array which holds the

net/core/net-sysfs.c

@@ -726,6 +726,7 @@ static struct kobj_type rx_queue_ktype = {
 static int rx_queue_add_kobject(struct net_device *net, int index)
 {
 	struct netdev_rx_queue *queue = net->_rx + index;
+	struct netdev_rx_queue *first = queue->first;
 	struct kobject *kobj = &queue->kobj;
 	int error = 0;
 
@@ -738,6 +739,7 @@ static int rx_queue_add_kobject(struct net_device *net, int index)
 	}
 
 	kobject_uevent(kobj, KOBJ_ADD);
+	atomic_inc(&first->count);
 
 	return error;
 }